Leaching effect of rainfall on soil under four-year saline water irrigation

Abstract

Cucci G., Lacolla G., Mastro M. A., Caranfa G. (2016): Leaching effect of rainfall on soil under four-year saline water irrigation. Soil & Water Res., In the context of the overall competition for water resources it is important to understand the complex dynamics of crop water management including evapotranspiration, water quality, and leaching requirement, each of them depending on the site-specific conditions. The research started with grain maize and continued with sunflower, grain maize, and wheat, at the experimental field. On both grain maize and sunflower, 10 irrigation treatments were compared that resulted from the factorial combination of two types of water (fresh and brackish water) with five irrigation regimes; the scheduled treatments were applied by furrow irrigation. The amount of salts brought into the soil with the irrigation water during the three irrigation seasons of our trial increased shifting from the lowest to the highest irrigation regime and with the increase of salinity in the irrigation water. From the study of salt distribution in the soil it follows that at the end of the irrigation season the salt concentration increased by passing from the middle of the furrow, a zone more subject to leaching during irrigation, to the intermediate zone between the furrow and the ridge, and in the middle of the ridge between two contiguous furrows, an area of confluence of the wetting and salt accumulation fronts. The leaching water supplied during the irrigation season was poorly efficient in leaching the salts brought in through irrigation, whereas the rainfall water of the autumn-winter period after the irrigation season ensured a good control of soil salinity.

Identifying the future water and salinity risks to irrigated viticulture in the Murray-Darling Basin, South Australia

“…Notably, most of the rainfall in the study area is received during winter season which may generate higher leaching fraction due to less evapotranspiration demand and hence greater salt leaching effect. Cucci et al (2016) also found similar impact of winter season rainfall under the Mediterranean climate in a sandy loam soil. Overall, the seasonal salinity and average salinity (1.97 dS/m) during the entire period of current climate (2004)(2005)(2006)(2007)(2008)(2009)(2010)(2011)(2012)(2013)(2014)(2015) remained below threshold (EC sw = 4.2 dS/m) for viticulture.…”

Groundwater Evaporation for Salt-Affected Soil Under Plastic Film-Covered Cultivation Condition: a Review

“…Besides, groundwater evaporation could be reflected via the capillary rise, which in turn reveals the mechanism involved in groundwater evaporation. In such areas, the salts in deep soil layers will move up to shallow layers driven by upward groundwater under evaporation; meanwhile, the salts will also probably be leached into groundwater under large amount of irrigation (Cucci et al 2016;Yang et al 2019). This interactive behavior ultimately causes soil salinization and groundwater pollution, which has become a main obstacle during sustainable agricultural development (Benini et al 2016;Xing and Ma 2018).…”

Spectroscopic Determination of Water Salinity in Brackish Surface Water in Nandoni Dam, at Vhembe District, Limpopo Province, South Africa

“…Other than estuaries, the elevated groundwater salinity can be observed in the regions where groundwater is in contact with evaporates formations, or mixed with high mineralized and deeper aquifers [8,9]. The discharges from industrial effluents containing dissolved salts, leachates of saline soils and the runoff of salt deposits such as halite or gypsum that is present in the sedimentary rocks also increase the amounts of total dissolved salts and thus lead to the formation of brackish water [10][11][12]. However, the primary contributing source of brackish surface water (e.g., brackish dam water) is the mixing of the saline water from the open wells and the fresh water as well as the flow from the saline aquifer sourced from pumping wells to the surface water [13].…”